When should I renew my .AT domain name?
Unlike most top-level domains (TLDs), .AT domains only allow you to register 1 year at a time. For this reason, you can't renew your .AT domain more than 1 year out from its expiration date and .AT domains must be renewed at least 5 days before their expiration date.
If you do not renew your .AT domain within this timeline, the domain will be removed from your Dynadot account and transferred into control of Nic.AT, the .AT central registry. If this happens, you will need to renew the domain directly through the central registry.